This invention relates to aeration devices for bulk storage containers, such as hoppers, tank cars, etc. to facilitate the discharge of dry material from the containers.
Many prior art devices are available for providing aeration to bulk materials stored within a container to stimulate their flow within the container. Obviously, such containers can comprise a tank trailer, railroad car, a vessel bulk storage area, and related types of devices that are used to convey and store primarily granular and dry materials in bulk quantities. Such bulk materials, by way of information may include cement, lime, flour, plastic resins, and any of a large variety of generally dry powdered and bulk type of material that needs to be conveyed, in massive amounts, but when they reach their destination, require assistance to provide for their discharge, from their storage containers.
For example, the applicant herein has obtained U.S. Pat. No. 5,017,053, upon an aeration device for bulk material containers. As shown therein, the aeration device comprises a molded plastic hollow body that has air permeable attributes. As pressurized air flows into the shown device, the air permeates through the molded body, to assist in the fluidizing of the granular material to stimulate its flow within its storage container. Usually, such storage containers will have either an arcuate, curved, or sloping base wall. Through the injection of pressurized air into the aeration device, or by vibratory movement of the aeration device, the granular material can achieve a fluid flow until all of it discharges from the hopper or other storage container.
An early bin aerator can be seen in the U.S. Pat. No. 3,952,956, which shows a vibrating rubber housing that is used to help dislodge materials from the walls of a bin during discharge. Other United States patents disclose related types of fluidizing means for transfer of powdered substances. One such device is shown U.S. Pat. No. 4,030,755. Another such device is shown in U.S. Pat. No. 3,343,888 to Anderson, et al.. The Anderson patent shows a hopper arrangement for pneumatically unloading containers of granular material. Once again, the object of these devices is to fluidize the powdered material to achieve and stimulate its flow, along a sloping surface, to the discharge exit of the storage container. U.S. Pat. No. 4,172,539 to Botkin shows another early style of aerator nozzle for use creating a fluidized flow of granular or powdered material. U.S. Pat. No. 4,189,262 to Anderson shows a variety of such aeration devices and apparatuses, and their method for handling dry bulk materials in a hopper-style container using air agitation to achieve fluid flow.
U.S. Pat. No. 3,929,261 to Solimar shows a further aeration device and method for assisting discharge of material from containers. The Solimar aeration device has a body formed into a conical shape upon which a flexible flapper valve mounts. When air under pressure is injected through the body, it flaps the valve, emitting pressurized air into the granular material, and likewise inducing vibratory flow, to achieve discharge of granular material from the shown conically shaped bottom of the disclosed hopper. While the shown Solimar device is effective for its intended purposes, one of the problems associated with it is that its body extension substantially reduces the effective size of the apertures through which the pressurized air may flow, and thus creates a back pressure. This has a detrimental effect in achieving the enhanced intended results sought from such an apparatus (i.e., to obtain a substantial flow of all of the pressurized air through the flapper member, and into the granular material, without any significant back pressure, in order to enhance fluid flow).
U.S. Pat. No. 4,662,543, also to Solimar, shows a related style of aeration device for assisting in the aeration of material from containers. As can be seen from this Solimar patent, this second Solimar device substantially reduces the air flow space by inserting a substantial sized anchor stud therethrough. This anchor stud is the means for mounting the aeration device to the wall of the container, during its installation. Hence, it has been found that significant back pressures of the generated air, that is intended to flow through the aeration device, to achieve its functionality, has a detrimental effect upon obtaining maximum efficiency of air flow, to achieve enhanced fluidized flow of the granular material from the shown container. Furthermore, in order to provide for the effectiveness as alleged from this patented device, it substantially weakens and reduces the peripheral edges of its skirt cup, in order to obtain a pointed type of contact under pressure with the surface of the interior of the shown container, or its intermediate plate, as noted, to prevent the presence of any reverse angle into which granular material may flow, and cause blockage to the normal flow the pressurized air, during usage of the shown air aeration device.
There are also other aeration devices available upon the market, such as is shown in U.S. Pat. No. 4,820,052, where the housing means for such devices are formed more of a cylindrical shape, and have their flapper valves, also of corresponding cylindrical configuration, mounted thereon in order to achieve vibrations of the valve, and flow of pressurized air, to effect fluidizing of the granular material to stimulate its movement. These are examples of the style of prior art devices that are available in the trade. While they are reasonably effective to achieve their intended purposes, the current invention is designed to substantially enhance the functionality and operations of such an aeration device by significantly reducing the back pressure of air passing through such a device, while at the same time affording better vibratory effects to its flapper valve to stimulate fluidizing of the granular material. In addition, the current invention will be substantially constructed in preassembled form, so as to provide all of its installing components substantially assembled together, ahead of time, and only require the installation of a mounting bolt, to attain final installation and assembly, as distinct from the prior art devices that require their piece meal assembly and time and labor consumption to achieve workable installation.